We propose to develop a novel computer-based system for performing simultaneous video imaging and patch-clamp recording from single cells and couplets. Although systems exist for the individual functions of fluorescence imaging, patch-clamp current recording and capacitance measurement, the synchronization and integration of these measurements in one experimental system has not been accomplished. We propose to develop such a system in three stages. In this proposal we request funding for the first two stages, which involve the design and implementation of the software that will control and synchronize the data collection and analysis for experiments: 1. Software design and patch-clamp interface. In the first year we intend to plan the architecture of the software, and to adapt as existing Macintosh-based patch-clamp acquisition program to work with the QuickTime synchronization system. 2. Implementation of quantitative image analysis. Work in the second year will be the adaptation of modules that perform fluorescence ratio and morphometric image processing to work in the QuickTime framework. These software developments form the basis for the third stage, the construction of the actual experimental setup.